CALGARY — Two groups opposed to a proposed dam and reservoir meant to help prevent flooding in southern Alberta are urging a friendly resolution to the dispute.

The Tsuut’ina Nation and the landowners organization Don’t Damn Springbank have sent an open letter to Calgary Mayor Naheed Nenshi and others about flood mitigation on the Elbow River.

The letter says everyone should get together like neighbours to find a solution to the ongoing argument about where to put the dam.

Nenshi has backed a provincial plan to build the dam at Springbank, 15 kilometres west of Calgary, saying it’s needed to protect the city from another flood.

The Tsuut’ina Nation and nearby communities such as Bragg Creek want it to be built further upstream.

The letter says one community shouldn’t be sacrificed for another.

The dam is one of the mitigation measures ordered by the Alberta government after devastating floods in June 2013. TsuuT’ina Chief Lee Crowchild has said water backing up during a flood diversion would flow over his people’s land and could cause groundwater contamination.

The plan calls for gates upstream of Calgary to divert water during flooding from the river into a canal that would lead to surrounding land. The water would be channelled back into the river when flooding subsides.

Some of the dozens of landowners opposed to the dam have had ranches in Springbank since the 1880s.

In June, the Federal Court of Canada sided with the landowners, who had argued that federal Environment Minister Catherine McKenna must decide whether there should be an independent review of the project.

The letter issued Wednesday says the decision to build at Springbank was rushed, politically motivated and sacrifices neighbouring communities.

It also questions the cost and points out it is already four years since the floods.

“Some claimed Springbank would be fast, easy and cheap,” says the letter signed by Crowchild and John Robinson, chairman of Don’t Damn Springbank. “It’s not cheap.

“New numbers from Alberta will show how the anticipated costs for Springbank are continuing to skyrocket.”

The letter also suggests the dam is facing growing opposition.

“We are inviting all groups to come together and … explore common ground for a solution that works for all communities,” it concludes.

“Let’s not lose sight of the neighbourly spirit that got us all through the floods. No communities deserve to be further damaged … there are other options.”

Heavy rain over two days in 2013 overwhelmed river systems in southern Alberta and the resulting deluge wiped out roads and bridges, swamped streets and damaged homes.